Francoise Vimeux & Florence Sylvestre 
Past Climate Variability in South America and Surrounding Regions 
From the Last Glacial Maximum to the Holocene

South America is a unique place where a number of past climate archives are ava- able from tropical to high latitude regions. It thus offers a unique opportunity to explore past climate variability along a latitudinal transect from the Equator to Polar regions and to study climate teleconnections. Most climate records from tropical and subtropical South America for the past 20, 000 years have been interpreted as local responses to shift in the mean position and intensity of the Inter Tropical Conv- gence Zone due to tropical and extratropical forcings or to changes in the South American Summer Monsoon. Further South, the role of the Southern Hemisphere westerly winds on global climate has been highly investigated with both paleodata and coupled climate models. However the regional response over South America during the last 20, 000 years is much more variable from place to place than pre- ously thought. The factors that govern the spatial patterns of variability on millennial scale resolution are still to be understood. The question of past natural rates and ranges of climate conditions over South America is therefore of special relevance in this context since today millions of people live under climates where any changes in monsoon rainfall can lead to catastrophic consequences.

Table des matières

Can We Draw a Robust Picture of Last Glacial Maximum Climate Conditions in South America?.- Moisture Pattern During the Last Glacial Maximum in South America.- Orbital and Millennial-Scale Precipitation Changes in Brazil from Speleothem Records.- Chronologies of the Last Glacial Maximum and its Termination in the Andes (?10–55°S) Based on Surface Exposure Dating.- Vegetation and Fire at the Last Glacial Maximum in Tropical South America.- Re-evaluation of Climate Change in Lowland Central America During the Last Glacial Maximum Using New Sediment Cores from Lake Petén Itzá, Guatemala.- Glacial to Holocene Paleoceanographic and Continental Paleoclimate Reconstructions Based on ODP Site 1233/Geo B 3313 Off Southern Chile.- The High Latitudes-Tropics and Tropics-Tropics Teleconnections over the Last Deglaciation and Last Glacial Maximum.- Teleconnections into South America from the Tropics and Extratropics on Interannual and Intraseasonal Timescales.- South American Climate Variability and Change: Remote and Regional Forcing Processes.- Sensitivity of South American Tropical Climate to Last Glacial Maximum Boundary Conditions: Focus on Teleconnections with Tropics and Extratropics.- Similarities and Discrepancies Between Andean Ice Cores Over the Last Deglaciation: Climate Implications.- Characteristics of the Holocene Climate. Focus on Global Events: Are They Widespread, Comparable and Synchroneous in South America?.- Mid-Holocene Climate of Tropical South America: A Model-Data Approach.- Millennial-Scale Ecological Changes in Tropical South America Since the Last Glacial Maximum.- The Nature and Origin of Decadal to Millennial Scale Climate Variability in the Southern Tropics of South America: The Holocene Record of Lago Umayo, Peru.- Hydrological Variability in South America Below the Tropic of Capricorn (Pampas and Patagonia, Argentina) During the Last 13.0 Ka.- Climate Change in Southern South America During the Last Two Millennia.- The Little Ice Age in Southern South America: Proxy and Model Based Evidence.